'FindKm.Bas
'Demo for MA01-MA2's alphabet
Al$ = "QNKBMFEGJHXCTDUAZWPYRLSVOI"
PrintKM Al$,4,10  'Print table of
End               'decimation scores

Sub PrintKM(Al$,N1,N2) 'PrintKM will
Hdr$=Space$(26)        'print scores
For N=N1 to N2         'for widths
  Hdr$=Hdr$+RJust$(N,5)'N1 to N2.
Next N       'Loop builds header
Print Hdr$   'string which we print.

For I=1 to 12       'For each of 12
  A$=NextDec$(Al$)  'odd decimations
  Row$=A$           'we build a row
  For N=N1 to N2    'of scores
    Row$=Row$+RJust$(KMScore(A$,N),5)
  Next N
  Print Row$        'Print scores
Next I              'next decimation
End  Sub 'PrintKM

'Returns next odd decimation of Al$
Function NextDec$(Al$) Static
If Al$<>A$ Then  'If Al$ or A$ has
   A$=Al$        'changed then start
   I=1           'with decimation 1
End If
If I=13 Then I=15'Skip decimation 13
Count=0 : J=1 : Dec$=""
While Count < 26        'Build next
  Dec$=Dec$+Mid$(A$,J,1)'decimation
  J= (J+I) mod 26       'one letter
  If J=0 Then J=26      'at a time
  Count=Count+1         'until count
Wend                    'is 26.
I=I+2                   'I=next odd
If I=27 Then A$="" 'Restart A$ after
NextDec$=Dec$      'final decimation
End Function 'NextDec$

'Returns score for Al$, block width N
Function KMScore(Al$,N)
Tmp$=Al$+Al$ : Score=0 
For I=1 to 26 'I is posn in alphabet
  Count=1     'Number of ltrs in unit
  For J=I to I+25 'J=posn in Ith unit
    CurLtr = ASC(Mid$(Tmp$,J,1))  
    NxtLtr = ASC(Mid$(Tmp$,J+1,1))
    If CurLtr+N >NxtLtr Then Exit For
    Count=Count+1 'Count ltr if block
  Next J          'width permits
  If Count > 1 then
     Score=Score + Count*Count
  End If
Next I
KMScore=Score
End Function 'KMScore

'Right-justify I in field of length L
Function RJust$(I,L)
  Tmp$=Space$(L)+Ltrim$(Str$(I))
  RJust$=Right$(Tmp$,L)
End Function 'RJust$